Piston engine



April 3, 1951 A. HOROWITZ ET AL 2,547,163

PISTON ENGINE Filed Oct. 20, 1948 2 Sheets-Sheet 1 April 3, 1951 A.oRowrrz ET AL 2,547,163

PISTON ENGINE Filed Oct. 20, 1948 2 Sheets-Shet 2 INVENTORS PatentedApr. 3, 1951 PISTON ENGlNE Alexandre Horowitz and Martinus Kooy,Eindhoven, Netherlands, assignors to Hartford National Bank and TrustCompany, Hartford,

Conn., as trustee Application October 20, 1948,S erial No. 55,548 In theNetherlands November 8, 1947 4 Claims. (Cl. 74 -50) Piston enginescomprising one or more pistons and in which the stroke of the pistons isdetermined by a member mounted eccentrically on the main shaft, areknown. In engines comprising a driving mechanism of this type, thepistons and the member mounted eccentrically on the main shaft mostlycomprise pressure or contact sur faces which co-operate and slide overeach other during operation of the engine. It is plain that an engine ofthis type in which, consequently, there is no' junction between thepistons on the one hand and the member determining the piston path onthe other hand, can be reduced to practic only if the force acting uponthe piston is constantly directed towards the main' shaft or, in otherwords, if the cooperating surfaces are constantly pressure loaded. Sincethese surfaces slide over each other during operation of the engine, itis necessary for them to be well lubricated in accordance with thecontact pressure. Since in view of a simple construction on the one handand easy assembly and disassembly on the other hand, it is oftenimpracticable to give these surfaces an unlimited size, the thrust perunit area may be high at high piston pressures, due to which thesolution of the lubrication problem, also in connection with the oftendifficult accessibility of the contact surfaces, is not simple. Even inthe case of perfect lubrication considerable losses due to friction mayoccur, notably if the contact surfaces are not processed to an extremelyhigh degree of accuracy, by which the cost of manufacture is greatlyincreased.

As is known, these disadvantages can be avoided in a piston-enginecomprising one or more pistons and in which the stroke of the pistons isdetermined by a member mounted eccentrically on the main shaft of theengine and of which one or more contact surfaces co-operate with one ormore other contact surfaces coupled with the pistons in such manner thatevery two co-operating contact surfaces are parallel, by providingexclusively rolling parts between two co-operating contact surfaces.These rolling parts may be enclosed in a cage in such manner as to beable to travel only a limited distance between th contact surfaces,which distance may be determined by means forming part of theeccentrically arranged member.

In a suitable construction according to the invention all cages in whichthe rolling parts are contained are interconnected, and one or more ofthe members provided with the contact surfaces comprise meansdetermining the path of 1 2 the cage with rolling parts which isprovided between these contact surfaces. 7

In a particularly suitable construction according to the invention allcages are interconnected by a member which is arranged eccentricallywith respect to the main shaft and rotatable about the latter, and ofwhich member the movement is moreover determined by a crank connectionbetween this member and the other member which is mounted eccentricallyon the mainshaft and is rotatable about the latter.

In order that the invention may be clearly understood and readilycarried into effect it will now be explained more fully with referenceto the accompanying drawings, given by way of example.

. Fig. 1 shows a construction according to the I invention, in which allcages are interconnected, and one contact surface comprises stopslimiting the path of the rolling parts.

. Fig. 2 shows another construction according to the invention, in whichalso all cages are interconnected, but the movement of the connectingmember is determined by a crank connection.

. Fig. 3 is a detail view of the construction of the projecting part onmember 2! shown in Fig. 2 on an enlarged scale.

Figure 4a represents another form of the contact surfaces.

Figure 412 represents still another form of the contact surfaces. In thedrawing corresponding parts bear the same reference numerals.

In Fig. 1 the reference numeral i denotes the main shaft which is drivenor by which a tool is driven. An eccentric 3 is secured to this mainshaft by means of a key 2. About this eccentric 3 is journalled a member4 which exhibits four contact surfaces 5, 6, i and 8. Furthermore, theengine comprises four pistons 9, It, i I, H! exhibiting contact surfacesl3, l4, l5 and. it. A needle bearing comprising needles I! provided in acage 48, is provided between the co-operating contact surfaces 5 and I3.Such a needle bearing is also provided between the surfaces 6 and M, iand I5, ands and Hi; The cage 58 comprises a pin I9.

A member 22 is mounted eccentrically on the main shaft I, with aneccentricity amounting to half that of the eccentric 3. A member 2icomprising four forked projecting parts 23 is rotatable about theeccentric 22. The pins I9 of the cages engage between thetwo teeth 23 ofthe said forks. One of the pistons l2 comprises stops 24, 2! limitingthe path of the cage It with the rolling elements ll, so that at. theend of the stroke any divergence is corrected. Since the cages conetaining the rolling elements are interconnected through the eccentricmember 2| with forks 23, all cages with rolling elements are held inposition.

Fig. 2 represents another construction according to the invention. Inthis construction the second eccentric member 22 is again provided asshown in Fig. 1, about which member the member 2! is journalled. In thiscase also the member 2i exhibits forks engaging about pins l9 secured tothe cages. In this construction the member 23 comprises, moreover, aprojecting part 28 (Fig. 3) which is provided with a pin 29. Theeccentric member 4 is provided with a groove 30 accommodating th pin 29.The radius of this groove 30 corresponds to the eccentricity of the saidmembers 2i and 22 and consequently to half the eccentricity of themember 4. In this manner, also, it is ensured that the cages IS withrolling elements H are able to travel only the distance required for therolling movement in both directions.

It is not necessary for the whole of the operating contact surfaces toextend in one plane, since constructions as shown in Figs. 4a and 4b arealso possible.

It is only necessary that the co-operating contact surfaces should beprismatic and more particularly cylindrical surfaces of which thegeneratrix coincides with the direction of motion.

What we claim is:

1. A piston engine comprising a plurality of separately movable pistons;means for determining the stroke of each of said pistons, said meanscomprising; a main engine shaft, a member journalled eccentrically onsaid main shaft, said member having a plurality of contact surfaces,each of said pistons having a contact surface which is operativelyassociated and parallel with one of said contact surfaces of said memberto form pairs of operatively associated contact surfaces, separaterolling means positioned between each pair of operatively associatedcontact surfaces and in rolling contact therewith, separate cage meansconfining each of said rolling means, common coupling means limiting thelateral movement of each of said cage means and the said rolling meansconfined thereby with respect to said operatively associated surfaces,said common coupling means being journalled on said main engine shaft.

2. A piston engine comprising a plurality of separately movable pistons;means for determining the stroke of each of said pistons, said meanscomprising a main engine shaft, a member journalled eccentrically onsaid main shaft, said member having a plurality of contact surfaces,each of said pistons having a contact surfact which is operativelyassociated and parallel with one of said contact surfaces of said memberto form pairs of operatively associated contact surfaces, separaterolling means positioned between each pair of operatively associatedcontact surfaces and in rolling contact therewith, separate cage meansconfining each of said rolling means, common coupling means limiting thelateral movement of each of said cage means and the said rolling meansconfined thereby with respect to said operatively associated surfaces,said common coupling means being journalled eccentrically on said mainengine shaft, and crank movement connection means coupling said commoncoupling means to said eccentrically journalled member for determiningthe movement of said common coupling means.

3. A piston engine comprising a plurality of separately movable pistons;means for determining the stroke of each of said pistons, said meanscomprising; a main engine shaft, a member journalled eccentrically onsaid main shaft, said member having a plurality of contact surfaces,each of said-pistons having a contact surface which is operativelyassociated and parallel with one of said contact surfaces of said memberto form pairs of operatively associated contact surfaces, separaterolling means positioned between each pair of operatively associatedcontact surfaces and in rolling contact therewith, separate cage meansconfining each of said rolling means, common coupling means limiting thelateral movement of each of said cage means and the said rolling meansconfined thereby with respect to said operatively associated surfaces,said common coupling means being journalled eccentrically on said mainengine shaft, and means mounted on one of said pistons for absolutelimitation of the lateral movement of the one of the cage meansassociated therewith.

4. A piston engine comprising a plurality of separately movable pistons;means for determining the stroke of each of said pistons, said meanscomprising; a main engine shaft, a member journalled eccentrically onsaid main shaft, said member having a plurality of contact surfaces,each of said pistons having a contact surface which is operativelyassociated and parallel with one of said contact surfaces of said memberto form pairs of operatively associated contact surfaces, separaterolling means positioned between each pair of operatively associatedcontact surfaces and in rolling contact therewith, separate cage meansconfining each of said rolling means, common coupling means limiting thelateral movement of each of said cage means and the said rolling meansconfined thereby with respect to said operatively associated surfaces,said common coupling means being journalled eccentrically on said mainengine shaft, and pin and slot connection means coupling said commoncoupling means to said eccentrically journalled member for determiningthe movement of said common coupling means.

ALEXANDRE HOROWITZ. MARTINUS KOOY.

REFERENCES orrEn The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

